The diffusion map finds new variables that reflect nonlinear combinations of metabolic capabilities and returns them in the order of their importance [1]}, [2]}. Each variable assigns coordinate entries to the genomes that can then be used to order genera, from the most negative to the most positive entries, along different niche dimensions. Dimensions can then be interpreted by analyzing the strategies of taxa near the extrema of the orderings [3]}, corresponding to large positive or negative (i.e. far from zero) variable entries.
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